THE AUTHOR'S OWN JOURNEY IN THE KURUK-TAGH. I05
Toghrak-kuduk. Only a short distance away begins the gentle slope which runs up to the sharply defined clay terrace that forms here the southern edge of the P'e-schan swelling (see fig. 71). On our right we left a detached portion of the same, resembling a projecting island in two stories. The soil between the edge of the zone of vegetation and the foot of the terrace is hard and strewn with gravel, and undulates a little. The terrace itself, which stretches in both directions as far as one can see, is on the top as level as a table, but its slope down towards the desert is on the contrary irregular, some portions of it shooting out like capes and headlands. It is also seamed by a great number of torrents and ravines, several of them pretty deep, and resembling gorges and »corridors». In places their ends gape upon one like gloomy portals. The only way to get to the summit of the terrace is by entering one of these and following it up to the top; the actual slopes themselves are much too steep to be climbed. At the point where we entered one of these ravines the terrace-wall was 35 m. high; if to this we add the height of the gently ascending saj, the total altitude is certainly i oo m. These trenches have been made by the occasional rain-torrents. Both they and the terrace itself resemble similar formations on the northern side of the Kuruk-darja. In both regions the clay terrace, or sag-is-jar, as the natives call it, is a dominant feature in the morphology of the country. One is tempted to regard it as a surviving portion of the shore of the great inland lake, of which the Kara-koschun is the last insignificant remnant. The material is yellowish brown, and consists of grains of quartz but little rounded. Probably it is a loess formation, notwithstanding the fact that the peculiar loess characteristics are not so pronounced as usual.
Generally speaking, the clay is quite soft, and bedded horizontally. This applies especially to the top layer, which however is firmer and more compact than the less regularly arranged layers underneath it, and these it accordingly protects. We traversed the lower parts of this soft clay region by a gently ascending gully, which was absolutely destitute of vegetation, although there were clear indications that a stream had flowed down it at no very distant date.
The upper part of the little valley stretched down from the north-west. Leaving this on our left, we soon reached more open country. Here we were separated by some flat, hard, gravelly hills from another gully, which ran S. 71° E., and was channelled to the depth of 3 m. Besides this there were a great number of smaller torrents no doubt all of them accessory to the principal ravine, although they had a more south-easterly direction. The locality was reminiscent of the foothills of Altmisch-bulak, except that the hills and elevations which we had on both sides of us here were lower and less important than those at the spring. As yet our view was not impeded by the ridges in the vicinity. Southwards we could distinguish faintly the different zones of the lowland saj, steppe, and sand; but we could see nothing whatever of the low foothills which lie in front of the Astin-tagh.
Soon afterwards we entered a fresh glen, 15o m. broad at its mouth, which led us towards the north. In its bottom, which was level, with an extremely gentle ascent, were pieces of driftwood washed down by the torrents; but of living vegetation not a sign. In places there were flat patches of mud, deposited by sheets of stagnant water. Eventually the glen grew narrower, about 8o m. across. On both
Hedin, yourney in Central Asia. II. 14
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